1Department of Periodontology, School of Dentistry, Chonnam National University, Korea.
2Department of Oral Biochemistry, School of Dentistry, Chonnam National University, Korea.
3Dental Science Research Institute School of Dentistry, Chonnam National University, Korea.
42nd stage of BK21 for School of Dentistry, Chonnam National University, Korea.
Corresponding author: Byung-Ju Park. Department of Oral Biochemistry, School of Dentistry, Chonnam National University, 5 Hakdong, Donggu, Gwangju, 501-190, Korea. bjpark@jnu.ac.kr